Virtual machines isolate an operating system from the computer platform that is used to execute the operating system. Operating systems running inside virtual machines can be executed by different computer platforms.
A single computer platform can support multiple virtual machines concurrently. Such a computer platform is commonly referred to as a logically partitioned platform. Each operating system or instance of an operating system is assigned a non-overlapping subset of the computer platform.
Typically, the multiple virtual machines are controlled by a hypervisor. The hypervisor can manage and enforce partition protection boundaries.
The state of a virtual machine can be stored (and restored) by using virtual machine check-pointing. The state of a virtual machine can be at least partially temporarily stored within various volatile memory units such as internal registers of the computer platform. The act of storing the state of the virtual machine is referred to as check-pointing. Accordingly, a snapshot of the state is stored in a non-volatile memory unit and can be retrieved when needed.
Restarting (“rebooting”) of computer systems is a procedure that can be executed in order to overcome acute failures or for other maintenance reasons. This procedure may normally take from several to tens of seconds to complete.
There is a need to speed up the booting sequence.